Animal Diversity Web

Ge­o­graphic Range

Snow­shoe hares are found through­out Canada and in the north­ern­most United States. The range ex­tends south along the Sier­ras, Rock­ies, and Ap­palachian moun­tain ranges. (Kurta, 1995; Wil­son and Ruff, 1999)

• Biogeographic Regions
• nearctic
  • native

Habi­tat

Snow­shoe hares are most often found in open fields, fence rows, swamps, river­side thick­ets, cedar bogs and conif­er­ous low­lands. (Kurta, 1995; Wil­son and Ruff, 1999)

• Habitat Regions
• temperate
• terrestrial

• Terrestrial Biomes
• tundra
• taiga
• forest

• Wetlands
• swamp
• bog

• Other Habitat Features
• agricultural

Phys­i­cal De­scrip­tion

Snow­shoe hares range in length from 413 to 518 mm, of which 39 to 52 mm are tail. The hind foot, long and broad, mea­sures 117 to 147 mm in length. The ears are 62 to 70 mm from notch to tip. Snow­shoe hares usu­ally weigh be­tween 1.43 and 1.55 kg. Males are slightly smaller than fe­males, as is typ­i­cal for lep­orids. In the sum­mer, the coat is a griz­zled rusty or gray­ish brown, with a black­ish mid­dor­sal line, buffy flanks and a white belly. The face and legs are cin­na­mon brown. The ears are brown­ish with black tips and white or creamy bor­ders. Dur­ing the win­ter, the fur is al­most en­tirely white, ex­cept for black eye­lids and the black­ened tips on the ears. The soles of the feet are densely furred, with stiff hairs (form­ing the snow­shoe) on the hind feet. (Kurta, 1995; Wil­son and Ruff, 1999)

• Other Physical Features
• endothermic
• homoiothermic
• bilateral symmetry

• Sexual Dimorphism
• female larger

• Range mass

  1.43 to 1.55 kg

  3.15 to 3.41 lb

• Range length

  413 to 518 mm

  16.26 to 20.39 in

• Average basal metabolic rate

  6.708 W

  AnAge

Re­pro­duc­tion

Groups of males con­gre­gate around es­trus fe­males, fol­low­ing the fe­males as they move about their home ranges. Mat­ing is polyg­y­nan­drous (both males and fe­males have mul­ti­ple mates). (Kurta, 1995; Wil­son and Ruff, 1999)

• Mating System
• polygynandrous (promiscuous)

Breed­ing sea­son for snow­shoe hares runs from mid-March through Au­gust, when the testes of the male begin to regress. Ges­ta­tion lasts 36 days. When par­tu­ri­tion ap­proaches, fe­male hares be­come highly ag­gres­sive and in­tol­er­ant of males. They re­tire to a birthing area, where they have pre­pared an area of packed down grasses. Fe­males give birth to lit­ters of up to 8 young, al­though the av­er­age lit­ter size is usu­ally two to four young. Lit­ters born late in the sea­son tend to be larger than lit­ters born in the spring. Fe­males are polye­strous and may have up to four lit­ters a year, de­pend­ing on en­vi­ro­men­tal con­di­tions. Males and fe­males be­come ma­ture within a year of their birth. (Kurta, 1995; Wil­son and Ruff, 1999)

• Key Reproductive Features
• iteroparous
• seasonal breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual
• fertilization
• viviparous

• Breeding interval

  Female snowshoe hares may give birth every month during the breeding season.

• Breeding season

  Breeding season for snowshoe hares runs from mid-March through August.

• Range number of offspring

  1 to 7

• Average number of offspring

  2.82

• Average number of offspring

  3

  AnAge

• Range gestation period

  36 to 40 days

• Average gestation period

  37.2 days

• Range weaning age

  14 to 28 days

• Range age at sexual or reproductive maturity (female)

  1 (high) years

• Range age at sexual or reproductive maturity (male)

  1 (high) years

Young snow­shoe hares are pre­co­cial. They are born fully furred and able to lo­co­mote. The young hide in sep­a­rate lo­ca­tions dur­ing the day, only com­ing to­gether for 5 to 10 min­utes at a time to nurse. The fe­male alone cares for them until they are weaned and dis­perse, about four weeks after they are born. (Kurta, 1995)

• Parental Investment
• precocial
• pre-fertilization
  • provisioning
  • protecting
    • female
• pre-hatching/birth
  • provisioning
    • female
  • protecting
    • female
• pre-weaning/fledging
  • provisioning
    • female
• pre-independence
  • provisioning
    • female

Lifes­pan/Longevity

In the wild as much as 85% of snow­shoe hares do not live longer than one year. In­di­vid­u­als may live up to 5 years in the wild. (Carey and Judge, 2002; Kurta, 1995)

• Range lifespan
  Status: wild

  5 (high) years

• Average lifespan
  Status: wild

  5.0 years

  Max Planck Institute for Demographic Research

Be­hav­ior

Snow­shoe hares are typ­i­cally soli­tary, but they often live at high den­si­ties, and in­di­vid­u­als share over­lap­ping home ranges. They are ac­tive at low light lev­els and so are most often seen out and about at dawn, dusk, and dur­ing the night. They are also ac­tive on cloudy days.

Dur­ing the day­light hours, hares spend a great deal of time groom­ing, and they take fit­ful naps. Most ac­tiv­ity is re­stricted to path­ways, tram­pled down "roads" in the veg­e­ta­tion that the hares know very thor­oughly.

Hares like to take dust baths. These help to re­move ec­topar­a­sites from the hares' fur.

Snow­shoe hares are also ac­com­plished swim­mers. They oc­ca­sion­ally swim across small lakes and rivers, and they have been seen en­ter­ing the water in order to avoid preda­tors. (Kurta, 1995; Wil­son and Ruff, 1999)

• Key Behaviors
• terricolous
• saltatorial
• nocturnal
• crepuscular
• motile
• sedentary
• solitary
• territorial

• Range territory size

  0.03 to 0.07 km^2

Home Range

Dur­ing its ac­tive pe­riod, a hare may cover up to 0.02 square kilo­me­ters of its 0.03 to 0.07 square kilo­me­ter home range.

Com­mu­ni­ca­tion and Per­cep­tion

Snow­shoe hares have acute hear­ing, which pre­sum­ably helps them to iden­tify ap­proach­ing preda­tors. They are not par­tic­u­larly vocal an­i­mals, but may make loud squeal­ing sounds when cap­tured. When en­gag­ing in ag­gres­sive ac­tivites, these an­i­mals may hiss and snort. Most com­mu­ni­ca­tion be­tween hares in­volves thump­ing the hind feet against the ground. (Kurta, 1995)

• Communication Channels
• acoustic

• Perception Channels
• visual
• tactile
• acoustic
• chemical

Food Habits

The diet of snow­shoe hares is vari­able. They browse on green grasses, forbs, blue­grass, brome, vetches, asters, jew­el­weed, wild straw­berry, pussy-toes, dan­de­lions, clovers, daisies and horse­tails. The new growth of trem­bling aspen, birches and wil­lows is also eaten. Dur­ing the win­ter, snow­shoe hares for­age on buds, twigs, bark, and ever­greens. They have been known to can­ni­bal­ize the re­mains of dead con­specifics in win­ter months. At all times, it is im­por­tant for hares to reingest cer­tain feces. Be­cause much of the di­ges­tion of food oc­curs in their hindguts, in order to ex­tract all of the avail­able nu­tri­ents from their food, they must cycle it through their di­ges­tive sys­tem a sec­ond time. (Kurta, 1995; Wil­son and Ruff, 1999)

• Primary Diet
• herbivore
  • folivore

• Animal Foods
• carrion

• Plant Foods
• leaves
• wood, bark, or stems
• flowers

• Other Foods
• dung

Pre­da­tion

Snow­shoe hares are ex­perts at es­cap­ing preda­tors. Young hares often "freeze" in their tracks when they are alerted to the pres­ence of a preda­tor. Pre­sum­ably, they are at­tempt­ing to es­cape no­tice by being cryp­tic. Given the hare's back­ground-match­ing col­oration, this strat­egy is quite ef­fec­tive. Older hares are more likely to es­cape preda­tors by flee­ing. At top speed, a snow­shoe hare can travel up to 27 mile per hour. An adult hare can cover up to 10 feet in a sin­gle bound. In ad­di­tion to high speeds, hares em­ploy skill­ful changes in di­rec­tion and ver­ti­cal leaps, which may cause a preda­tor to mis­judge the exact po­si­tion of the an­i­mal from one mo­ment to the next.

Im­por­tant preda­tors of snow­shoe hares in­clude gray foxes, red foxes, coy­otes, wolves, lynx, bob­cats and mink. (Kurta, 1995; Wil­son and Ruff, 1999)

• Anti-predator Adaptations
• cryptic

• Known Predators

  • coyotes (Canis latrans)
  • wolves (Canis lupus)
  • lynx (Lynx canadensis)
  • bobcats (Lynx rufus)
  • mink (Neovison vison)
  • red foxes (Vulpes vulpes)
  • grey foxes (Urocyon cinereoargenteus)

Ecosys­tem Roles

Snow­shoe hares are im­por­tant prey an­i­mals in their ecosys­tem. (Kurta, 1995; Wil­son and Ruff, 1999)

Eco­nomic Im­por­tance for Hu­mans: Pos­i­tive

Snow­shoe hares are uti­lized widely as a source of wild meat. In ad­di­tion to this, they are an im­por­tant prey species for many preda­tors whose furs are highly val­ued. (Kurta, 1995)

• Positive Impacts
• food

Eco­nomic Im­por­tance for Hu­mans: Neg­a­tive

Hares may dam­age trees, es­pe­cially dur­ing pe­ri­ods of high pop­u­la­tion den­sity. (Kurta, 1995)

Con­ser­va­tion Sta­tus

Snow­shoes hares are com­mon through­out their range. Their rapid re­pro­duc­tion makes it un­likely that they will be­come a major con­cern for con­ser­va­tion­ists. (Kurta, 1995; Wil­son and Ruff, 1999)

• IUCN Red List

  Least Concern
  More information

• IUCN Red List

  Least Concern
  More information

• US Federal List

  No special status

• CITES

  No special status

• State of Michigan List

  No special status

Other Com­ments

Snow­shoe hares have been widely stud­ied. One of the more in­ter­est­ing things known about hares are the dra­matic pop­u­la­tion cy­cles that they un­dergo. Pop­u­la­tion den­si­ties can vary from 1 to 10,000 hares per square mile. The am­pli­tude of the pop­u­la­tion fluc­tu­a­tions varies across the ge­o­graphic range. It is great­est in north­west­ern Canada, and least in the rocky Moun­tain re­gion of the United States, per­haps be­cause there is more bi­o­log­i­cal di­ver­sity in more southerly re­gions. The lack of di­ver­sity in the North­west­ern por­tion of the hare's range means that there are fewer links in the food chain, and there­fore fewer species to buffer ei­ther dra­matic pop­u­la­tion in­creases or de­creases. Dis­ease may play a part in pop­u­la­tion fluc­tu­a­tion. Pneu­mono­coc­cus, ring­worm, and sal­mo­nella have all been as­so­ci­ated with pop­u­la­tion crashes.

Snow­shoe hares are also fa­mous for their sea­sonal molts. In the sum­mer, the coat of the hare is red­dish brown or gray, but dur­ing the win­ter, the coat is snowy white. The molt usu­ally takes about 72 days to reach com­ple­tion, and it seems to be reg­u­lated by daylength. In­ter­est­ingly, there seem to be two en­tirely dif­fer­ent sets of hair fol­li­cles, which give rise to white and brown hairs, re­spec­tively. (Kurta, 1995; Wil­son and Ruff, 1999)

Con­trib­u­tors

Al­li­son Poor (ed­i­tor), Uni­ver­sity of Michi­gan-Ann Arbor.

Nancy Shef­ferly (au­thor), An­i­mal Di­ver­sity Web.

Ref­er­ences

Baker, R.H. 1983. Mam­mals of Michi­gan. Michi­gan State Uni­ver­sity Press.

Ban­field, A.W.F. 1981. The Mam­mals of Canada. Toronto Uni­ver­sity Press. Toronto, Buf­falo.

Carey, J., D. Judge. 2002. "Longevity Records: Life Spans of Mam­mals, Birds, Am­phib­ians, Rep­tiles, and Fish" (On-line). Max Planck In­sti­tute for De­mo­graphic Re­search. Ac­cessed May 18, 2007 at http://​www.​demogr.​mpg.​de/​.

Kurta, A. 1995. Mam­mals of the Great Lakes Re­gion. Ann Arbor: Uni­ver­sity of Michi­gan Press.

Wil­son, D., S. Ruff. 1999. The Smith­son­ian Book of North Amer­i­can Mam­mals. Wash­ing­ton, D.C.: The Smith­son­ian In­sti­tu­tion Press.